This proposal is for the purchase of a Moor Instruments Vascular Assessment System (VAS), which will serve 7 NIH-funded research groups. The VAS is an integrated laser Doppler imaging (LDI) device that will replace our first generation Moor LDI system, which has been working at near maximum capacity for 8 years, but is outdated and produces data of inferior quality due to the low resolution images generated. An additional limitation of the present system is the wavelength of the laser does not penetrate past the most superficial tissue layers and, therefore, does not adequately interrogate the areas of interest. Finally, the present modality does not allow real-time capture of images for determining transient changes in blood flow due to interventions. The demand for LDI on our campus continues to grow, and the proposed system will fulfill the needs of a large number of researchers by providing excellent resolution of vascular beds, allowing assessment of deep tissue microcirculatory systems and providing serial, non-invasive dynamic visualization and quantitation of blood flow, so that new applications for LDI can be accommodated or developed. The VAS can image specimens with very high resolution (less than 100 mm), penetrate up to 3 mm in depth and can capture up to 25 frames per second of video. A typical scan takes only about 15 minutes (including preparation of animal model), and the system comes with an analysis workstation to allow rapid quantitation. The enhanced capabilities of the system will better serve the needs of our vascular biology research community. Applications for the proposed facility include: 1) Assessment of stem cell-induced revascularization of ischemic tissues. 2) Stem and progenitor cell-mediated vasculogenesis in tissue and cell grafts. 3) Serial evaluation of tumor perfusion in response to anti-angiogenic agents 4) Involvement of a bone marrow-derived cell population in neovascularization. 5) Evaluate the contribution of different endothelial progenitor types in vascular remodeling and angiogenesis. 6) Determination of the molecular mechanisms that contribute to disease-associated attenuation of endothelial repair processes and vasoreactivity. The acquisition of the VAS is essential for continued progress on these and future projects requiring this state-of-the-art technology. PUBLIC HEALTH RELEVANCE: This proposal is for purchase of a new laser Doppler imaging system, which will be used to study biological specimens from several laboratories. This technology will make possible new discoveries in the areas of vascular disease, blood homeostasis, assess the activity of compounds that alter blood flow, vascular remodeling and arteriogenesis in normal and diseased tissues.